Authorities in Pakistan reported Monday that gunmen targeted vaccination teams in northwestern districts during a nationwide campaign against the paralytic poliovirus, resulting in the deaths of at least one health worker and two police officers.

The violence in the militancy-hit Khyber Pakhtunkhwa province, which borders Afghanistan, also injured several polio workers and police force members escorting them. There were no immediate claims of responsibility for the attacks.

Pakistan has reported a significant surge in poliovirus infections in 2024, confirming 63 cases so far, compared to only six cases in 2023.

On Monday, the country launched a weeklong house-to-house vaccination campaign, culminating the year’s anti-polio efforts. Officials said the campaign aims to inoculate more than 44 million children under five to protect them against polio.

Ayesha Raza Farooq, the prime minister’s adviser for the polio eradication program, emphasized parental cooperation to help achieve a polio-free Pakistan.

“We strongly encourage all parents to welcome our dedicated polio workers when they visit your residence and ensure that your children under the age of five receive the necessary two doses of the polio vaccine,” she said.

The World Health Organization lists Pakistan and Afghanistan as the only two countries where the potentially fatal poliovirus continues to cripple children.

WHO officials have cited multiple factors for the resurgence of polio cases in Pakistan. They noted that false propaganda that anti-polio campaigns are a Western plot to sterilize Muslim children has led to vaccine boycotts in some Pakistani districts.

Additionally, insurgents in violence-hit regions occasionally stage deadly attacks on polio teams, suspecting them of spying for the Pakistani security forces, routinely disrupting vaccination drives.

“There are concerning numbers of missed children during the recent campaigns (ranging from 5,000 to 700,000) due to insecurity, boycotts, and program quality issues,” the WHO reported in a statement in August after an emergency committee meeting under the International Health Regulations.

Pakistani authorities have reported the killings of more than 200 polio workers and police personnel escorting them since the country launched vaccination campaigns in the 1990s to control infections.

WHO and officials in Afghanistan have reported at least 23 polio cases in 2024, up from six last year.

In September, the de facto Taliban government abruptly banned the house-to-house vaccination campaign in parts of the war-torn country, permitting only site-to-site and mosque-to-mosque vaccinations of Afghan children.

The WHO committee meeting lamented in its December 3 statement that the Taliban’s ban dealt a setback to the “very encouraging progress” made in Afghanistan during the first half of 2024.

“The committee was concerned about this recent development since site-to-site campaigns are not able to reach all the children in Afghanistan, especially those of younger age and girls,” said the statement. It warned that the restriction poses a substantial risk of a further resurgence of paralytic poliovirus in Afghanistan and beyond.